I gave my entire set-up a thorough cleansing and it seems that my heating element was dirtier than I thought. What I thought was a thin black film ended up being a cake of char. My plastic brush didn't touch it so I upgraded to a wire brush, which still didn't do the job. I ended up scraping it with sand paper for 45 minutes before it looked like new. I'm going to bet this imparted some nastiness to my last couple brews.

Right on! I am thinking your problems in this area are probably solved.